Federal Communications CommissionFCC 05-199
Report To Congress
The Satellite Home Viewer Extension
And Reauthorization Act Of 2004
Study Of
Digital Television Field Strength Standards
And
Testing Procedures
ET Docket No. 05-182
Adopted: December 6, 2005Released: December 9, 2005
Table of Contents
Paragraph
I.SUMMARY...... 1
II.BACKGROUND...... 3
III.THE DIGITAL TV SIGNAL STRENGTH STANDARDS...... 10
IV.DIGITAL TELEVISION FIELD STRENGTH MEASUREMENT PROCEDURES...... 109
V.PREDICTIVE MODELING...... 132
Page
APPENDIX A
Section 339(c)(1) of the Communications Act of 1934, As Amended...... A-1
APPENDIX B
Parties Submitting Comments and Reply Comments...... B-1
APPENDIX C
Tests of ATSC 8-VSB Reception Performance of Consumer Digital Television Receivers
Available in 2005...... C-1
APPENDIX D
Notice of Inquiry...... D-1
APPENDIX E
Comments and Reply Comments to Notice of Inquiry...... E-1
ACKNOWLEDGEMENTS
This Report was prepared under the leadership of the Office of Engineering and Technology, in cooperation with the Media Bureau.
Office of Engineering and Technology
Ron Chase, Bruce Franca, Charles Iseman, Ira Keltz, Stephen Martin, Alan Stillwell, David Sturdivant
Media Bureau
Eloise Gore
I.SUMMARY
1.Section 204(b) of the Satellite Home Viewer Extension and Reauthorization Act of 2004 (SHVERA) requires that the Federal Communication Commission (Commission) conduct an inquiry and develop recommendations regarding whether the Commission’s digital signal strength standard and the signal testing procedures used to identify if a household is “unserved” for purposes of the satellite statutory copyright license for distant digital signals should be revised.[1] This Report is in fulfillment of Congress’ directives to the Commission in Section 204(b) of the SHVERA.
2.Consistent with the SHVERA Section 204(b) directives, the Report describes the results of the Commission’s study and Inquiry on this matter and the Commission’s findings regarding whether changes should be made to the statutes or the Commission’s rules. As set forth in detail below, the Commission specifically finds that:
- No specific changes are needed to the digital television field strength standards and/or planning factors for purposes of determining whether a household is eligible to receive retransmitted distant network television signals.
- The Commission should conduct a rule making proceeding to specify procedures for measuring the field strength of digital television signals at individual locations that are generally similar to the current procedures for measuring the field strength of analog television stations. Certain modifications to those procedures are needed, however, to address differences in analog and digital television signals. The proper procedures for measuring digital television signals would be developed through the recommended rulemaking proceeding.
- The existing improved Individual Location Longley-Rice (ILLR) model should be used for predicting whether a household is unserved by digital television signals. The Commission specifically recommends that Congress amend the copyright law, as well as the Communications Act, to allow a predictive model to be used in connection with eligibility for a distant digital signal. The Commission further recommends that Congress provide the Commission with authority to adopt the existing improved ILLR model as a predictive method for determining households that are unserved by local digital signals for purposes of establishing eligibility to receive retransmitted distant network signals under the SHVERA.
The Report also includes a study of digital television receiver performance, attached hereto as Appendix C, that, inter alia, finds that there is no relationship between the ability of currently available digital television receivers’ to receive over-the-air signals and the prices of those receivers.
II.BACKGROUND
3.Broadcast television stations have rights, under the Copyright Act[2] and private contracts, to control the distribution of the national and local programming that they transmit. In 1988, Congress adopted the Satellite Home Viewer Act (SHVA) as an amendment to the Copyright Act in order to protect the broadcasters' interests in their programming while simultaneously enabling satellite carriers to provide broadcast programming to those satellite subscribers who are unable to obtain broadcast network programming over the air. Under the SHVA, these subscribers were generally considered to be "unserved" by their local stations. In the SHVA, Congress linked the definition of "unserved households" to a Commission-defined measure of analog television signal strength known as "Grade B intensity."[3] The Grade B signal intensity standard, as set forth in Section 73.683(a) of the Commission’s rules, is used to identify a geographic contour that defines an analog television station’s service area.[4] For digital television stations, the counterpart to the Grade B signal intensity standards for analog television stations are the values set forth in Section 73.622(e) of the Commission's Rules describing the DTV noise-limited service contour.[5]
4.The new Section 339 requires the Commission to conduct an inquiry regarding whether, for purposes of identifying if a household is unserved by a digital signal under Section 119(d)(10) of Title 17, United States Code, the digital signal strength standards in Section 73.622(e)(1) of the Commission’s rules, or the testing procedures in Section 73.686(d) of the Commission’s rules, should be revised to take into account the types of antennas that are available to consumers.[6] In 1999, the Commission adopted a Report and Order (SHVA Report and Order) addressing three major issues that arose in the context of the SHVA and several pending court actions and petitions to the Commission.[7] First, it affirmed the existing definition of a signal of Grade B intensity for use in determining eligibility for reception of distant network signals. Second, the Commission adopted rules for determining whether a household is able to receive an analog television signal of this strength.[8] In particular, the Commission adopted rules establishing a standardized method for measuring the strength of analog television signals on-site at individual locations. And finally, it endorsed a method for predicting the strength of such signals that could be used in place of actually taking measurements.[9]
5.As added under the Satellite Home Viewer Improvement Act of 1999 (SHVIA),[10] the then-new Section 339(c)(3) of the Communications Act required that the Commission develop and prescribe by rule a point-to-point predictive model for reliably and presumptively determining the ability of individual locations to receive signals in accordance with the signal intensity standard in effect under Section 119(d)(10)(A) of Title 17 of the Unites States Code, that is, the Grade B standards.[11] Section 339(c)(3) further required that the Commission rely on the ILLR model which the Commission had earlier developed for such predictions and that the Commission ensure that such model takes into account terrain, building structure, and other land cover variations. In response to these provisions, the Commission adopted a First Report and Order in May 2000 in which it amended its rules to prescribe use of an improved point-to-point ILLR model for establishing whether individual households are eligible to receive distant analog network television signals.[12] This model includes adjustments for land use and land cover loss values. The rules also provide for a neutral and independent entity to evaluate the qualifications of potential testers to conduct on-site signal strength measurements in cases where a network television station denies a subscriber’s request for a waiver of the ILLR prediction that the viewer is “served.”
6.In addition, in the SHVIA Congress directed the Commission to conduct an inquiry and prepare a report regarding the broadcast TV signal strength standard used for satellite carrier purposes. The then-new Section 339(c)(1) of the Communications Act required that this investigation evaluate all possible standards and factors for determining eligibility to receive retransmitted network station signals and, if appropriate, recommend modification of, or alternative standards or factors, to the Grade B intensity standard for analog television signals and to make a further recommendation relating to an appropriate standard for digital television signals.[13] In response to this directive, the Commission inquired into and evaluated the possible standards and factors for determining eligibility of households to receive retransmissions of network station signals by satellite carriers. It specifically considered whether to recommend modifications to, or alternative standards or factors for, the Grade B intensity standard for analog television signals. On November 29, 2000, the Commission issued a Report to Congress (SHVIA Report) in which it recommended retention of the Grade B signal intensity standard and eight of the nine planning factors used in developing that standard as the basis for predicting whether a household is eligible to receive retransmitted distant TV network analog signals under the SHVIA.[14] The Commission recommended modification of the remaining planning factor (time fading) by replacing the existing fixed values with location-dependent values determined for the actual receiving locations using the Individual Location Longley-Rice (ILLR) prediction model. With regard to digital signals, the Commission found that it would be premature to construct a distant network signal eligibility standard for DTV signals at that time. The Commission therefore recommended that establishment of a distant network signal eligibility standard for digital signals be deferred until such time as more substantial DTV penetration is achieved and more experience is gained with DTV operation.[15]
7.In December 2004, Congress enacted the SHVERA, which revised the statutory provisions of the SHVA and SHVIA, including Section 339 of the Communications Act of 1934.[16] Under the SHVERA, viewers in individual households who are not able to receive network digital television signals over-the-air from local television stations and who are in circumstances that meet certain additional qualifying criteria are eligible to receive those digital network television signals from distant stations carried via satellite. It is therefore important that the standard for determining whether a local digital television station’s signal strength at a specific location is sufficient for reception of service and that the procedures for evaluating digital television signal strength provide an accurate means for determining whether a household can receive a local network station’s digital signal. Subsection 339(a)(2)(D)(vi), as revised by SHVERA, provides that the digital signal strength standard defined in Section 73.622(e) of the Commission’s rules shall serve as the basis for determining whether a satellite TV subscriber is eligible to receive retransmitted distant TV network digital signals.[17] Section 73.622(e)(1) provides that the service area of a DTV station is the geographic area within the station’s noise-limited F(50, 90) contour where its signal is predicted to exceed the noise-limited service level.[18] Within this contour, service is considered available at locations where the station’s signal strength, as predicted using the terrain dependent Longley-Rice point-to-point propagation model, exceeds the following noise-limited service levels:[19]
Channels 2-6 (low-VHF)...... 28 dBu
Channels 7-13 (high-VHF)...... 36 dBu
Channels 14-69 (UHF)...... 41 dBu
8.Subsection 339(c)(1), as revised by the SHVERA, requires the Commission, not later than December 8, 2005, to complete an inquiry and submit a report recommending whether, for purposes of identifying if a household is unserved by an adequate digital signal, the digital signal strength standard set forth in Section 73.622(e)(1) of the Commission’s Rules or the testing procedures in Section 73.686(d) of the Commission’s Rules should be revised to take into account the types of antennas that are available to consumers.[20] Subsection 339(c)(1) requires that, in conducting the required study, the Commission consider six specific issues relating to the question of digital signal strength in the context of the “unserved household”:[21]
- Whether to account for the fact that an antenna can be mounted on a roof or placed in a home and can be fixed or capable of rotating;
- Whether the Commission’s rules should be amended to create different procedures for determining if the requisite digital signal strength is present than for determining if the requisite analog signal strength is present;
- Whether a standard should be used other than the presence of a signal of a certain strength to ensure that a household can receive a high-quality picture using antennas of reasonable cost and ease of installation;
- Whether to develop a predictive methodology for determining whether a household is unserved by an adequate digital signal;
- Whether there is a wide variation in the ability of reasonably priced consumer digital television sets to receive over-the-air signals, such that at a given signal strength some may be able to display high-quality pictures while others cannot, whether such variation is related to the price of the television set, and whether such variation should be factored into setting a standard for determining whether a household is unserved by an adequate digital signal; and
- Whether to account for factors such as building loss, external interference sources, or undesired signals from both digital television and analog television stations using either the same or adjacent channels in nearby markets, foliage, and man-made clutter.
The above specifications for study address three separate but interrelated concerns: 1) the appropriateness of the DTV planning factors that underlie the DTV signal strength standard, 2) the appropriateness of the objective test-site methodology for measuring digital signals, and 3) whether a predictive model should be developed for determining whether a household is unserved by an adequate digital TV signal for purposes of eligibility to receive distant network TV signals.
9.On April 29, 2005, the Commission initiated an inquiry to gather information pursuant to Section 339(c)(1).[22] The Commission received 9 comments and 5 reply comments in response to its Notice of Inquiry (Inquiry) in this proceeding. The results of the Commission’s study and analysis of the record of its Inquiry and other research and information in this matter and its recommendations are described in the following sections of this Report. These sections address the digital signal strength standards, testing procedures, and predictive models and specifically include consideration of the six issues that Congress specifically asked the Commission to address in Section 204 of the SHVERA.
III.THE DIGITAL TV SIGNAL STRENGTH STANDARDS
10.Eligibility to receive distant network signals retransmitted by a satellite carrier has been, in principle, based on the inability of a household subscribing to a Direct Broadcast Satellite (DBS) service is not able to receive network signals over-the-air at its location using a receiving system that conforms to the assumed receiving system on which the television service area standards are based.[23] If a household is not able to receive a network signal at a field strength level equal to or greater than the TV service area Grade B (analog TV) or noise-limited (digital TV) standards, that household may be eligible to receive the signal of a distant station affiliated with that network that is retransmitted on the household’s DBS service if it meets other criteria for eligibility. Congress has asked the Commission to investigate whether the noise-limited DTV service standard should be revised to take into account the types of antennas that are available to consumers. In considering this issue, the Commission must consider: 1) whether to account for the fact that an antenna can be mounted on a roof or placed in a home and can be fixed or capable of rotating, 2) whether there is a wide variation in the ability of reasonable priced consumer digital television sets to receive over-the-air signals such that at a given signal strength some may be able to display high-quality pictures while others may not, whether such variation is related to the price of the television set, and whether such variation should be factored into setting a standard for determining whether a household is unserved by an adequate digital signal, and 3) whether to account for factors such as building loss, external interference sources, or undesired signals from both digital television and analog television stations using either the same or adjacent channels in nearby markets, foliage, and man-made clutter. In this section, we discuss the digital TV signal strength standards and evaluate the factors underlying those standards, including those specified in Section 204, in light of our Inquiry and study. We also consider whether any adjustments to those standards are warranted in light of our findings.
A. The DTV Service Area Field Strength Intensity Standards
11.As indicated above, the service areas of broadcast television stations, in the absence of interference, are defined on the basis of a concept known as “noise-limited” service. Under this concept, a TV station’s service extends to cover geographic locations out to the edge of where reception is no longer possible because of interference from background electrical noise. The background noise limiting reception of service arises both from the environment and from within the equipment used to receive service. Both the analog TV Grade B field strength intensity standards and the digital TV noise-limited field strength intensity standards are defined on this basis. These standards were developed in the early days of both methods of television modulation as a key component of the Commission’s television station channel allotment and service area regulations.[24] The DTV service area definitions further specify that service is considered to be present in areas within the noise-limited contour where signal strength is predicted to exceed the noise-limited signal level using the terrain-dependent Longley-Rice point-to-point propagation model.[25]
12.The field strength of television signals decreases with distance from the transmitter and varies across individual locations and time. At locations close to a station’s transmitter the variation of signal strength across time and location are generally not great. However, as distance increases, the variability of the available signal strength with both location and time increases significantly. At the edge of a station’s service area, its signal will be available in some locations more of the time than at others. Historically, if service is not available all, or most of the time, it is simply considered not available. Under both the analog Grade B and digital noise-limited F(50,90) service standards, an acceptable television picture and sound service is available at 50% of the locations for 90% of the time at locations on the outer edge of a station’s service area. The signal strength values of the analog TV standards were selected to provide service at these levels of availability and the digital television standards were specified to enable DTV stations to replicate their analog service.[26]